Surfactant Science and Technology

DREW MYERS obtained his Ph.D. in Organic Chemistry with secondary specialization in Medicinal Chemistry at the University of Utah in 1974 and his M.Sc. in Surface and Colloid Science at the University of Bristol in 1979. He has been a consultant in surface, colloid, organic, and polymer chemistry since 1986.

• Preface xv1 An Overview of Surfactant Science and Technology 11.1 A Brief History of Surfactant Science and Technology 31.2 Surfactants in the Modern World 51.3 The Economics of Surfactant Science and Technology 81.4 The Near-Term Economic and Technological Future for Surfactants 101.5 Surfactantsin the Environment 111.6 A Surfactant Glossary 132 The Classification of Surfactants 172.1 The Basic Structure of Amphiphilic Molecules 172.2 A Systematic Classification of Surfactants 192.2.1 Surfactant Solubilizing Groups 192.2.2 Making a Choice 212.3 The Generic Anatomy of Surfactants 212.3.1 The Many Faces of Dodecane 222.3.2 Surfactant Solubilizing Groups 252.3.3 Common Surfactant Hydrophobic Groups 262.3.3.1 The Natural Fatty Acids 272.3.3.2 Saturated Hydrocarbons or Paraffins 282.3.3.3 Olefins 282.3.3.4 Alkyl Benzenes 292.3.3.5 Alcohols 292.3.3.6 Alkyl Phenols 302.3.3.7 Polyoxypropylenes 302.3.3.8 Fluorocarbons 312.3.3.9 Silicone Surfactants 322.3.3.10 Miscellaneous Biological Structures 322.4 The Systematic Classification of Surfactants 332.5 Anionic Surfactants 342.5.1 Sulfate Esters 352.5.1.1 Fatty Alcohol Sulfates 362.5.1.2 Sulfated Fatty Acid Condensation Products 362.5.1.3 Sulfated Ethers 372.5.1.4 Sulfated Fats and Oils 382.5.2 Sulfonic Acid Salts 392.5.2.1 Aliphatic Sulfonates 392.5.2.2 Alkyl Aryl Sulfonates 402.5.2.3 α-Sulfocarboxylic Acids and Their Derivatives 422.5.2.4 Miscellaneous Sulfo-Ester and Amide Surfactants 432.5.2.5 Alkyl Glyceryl Ether Sulfonates 462.5.2.6 Lignin Sulfonates 462.5.3 Carboxylate Soaps and Detergents 462.5.4 Phosphoric Acid Esters and Related Surfactants 482.6 Cationic Surfactants 492.7 Nonionic Surfactants 512.7.1 Polyoxyethylene-Based Surfactants 512.7.2 Derivatives of Polyglycerols and Other Polyols 522.7.3 Block Copolymer Nonionic Surfactants 542.7.4 Miscellaneous Nonionic Surfactants 542.8 Amphoteric Surfactants 552.8.1 Imidazoline Derivatives 562.8.2 Surface-Active Betaines and Sulfobetaines 572.8.3 Phosphatides and Related Amphoteric Surfactants 583 Surfactant Chemical Structures: Putting the Pieces Together 613.1 Surfactant Building Blocks 613.2 A Surfactant Family Tree 633.2.1 The Many Faces of Dodecane 633.3 Common Surfactant Hydrophobic Groups 663.3.1 The Natural Fatty Acids 673.3.2 Paraffins or Saturated Hydrocarbons 673.3.3 Olefins 673.3.4 Alkylbenzenes 683.3.5 Alcohols 693.3.6 Alkylphenols 703.3.7 Polyoxypropylene 703.3.8 Fluorocarbons 703.3.9 Silicone-Based Surfactants 723.3.10 Nonchemically Produced, a.k.a. “Natural” Surfactants 744 Natural Surfactants and Biosurfactants 754.1 What Makes a Surfactant “Natural”? 764.2 Surfactants Based on a Natural Sugar-Based Polar Head Groups 784.3 Biosurfactants 804.3.1 Biosurfactants as Nature Makes Them 804.3.2 Properties of Biosurfactants 814.3.3 Biosurfactant Classification 834.3.4 Some Aspects of Biosurfactant Production 844.3.5 Some Factors Affecting Biosurfactant Production 854.4 Biosurfactant Applications 874.5 Potential Limitations on the Commercial Use of Biosurfactants 904.6 Some Opportunities for Future Research and Development 904.7 Some Observations About the Future of Biosurfactants 905 Fluid Surfaces and Interfaces 935.1 Molecules at Interfaces 955.2 Interfaces and Adsorption Phenomena 975.2.1 A Thermodynamic Picture of Adsorption 975.2.2 Surface and Interfacial Tensions 995.2.3 The Effect of Surface Curvature 1015.2.4 The Surface Tension of Solutions 1025.2.5 Surfactants and the Reduction of Surface Tension 1035.2.6 Efficiency, Effectiveness, and Surfactant Structure 1056 Surfactants in Solution: Self-Assembly and Micelle Formation 1156.1 Surfactant Solubility 1166.2 The Phase Spectrum of Surfactants in Solution 1196.3 The History and Development of Micellar Theory 1236.3.1 Manifestations of Micelle Formations 1246.3.2 Thermodynamics of Dilute Surfactant Solutions 1276.3.3 Classical Theories of Micelle Formation 1286.3.4 Free Energy of Micellization 1296.4 Molecular Geometry and the Formation of Association Colloids 1306.5 Experimental Observations of Micellar Systems 1336.5.1 Micellar Aggregation Numbers 1336.5.2 The Critical Micelle Concentration 1356.5.3 The Hydrophobic Group 1356.5.4 The Hydrophilic Group 1436.5.5 Counterion Effects on Micellization 1456.5.6 The Effects of Additives on the Micellization Process 1466.5.6.1 Electrolyte Effects on Micelle Formation 1476.5.6.2 The Effect of pH 1486.5.6.3 The Effects of Added Organic Materials 1496.5.7 The Effect of Temperature on Micellization 1516.6 Micelle Formation in Mixed Surfactant Systems 1536.7 Micelle Formation in Nonaqueous Media 1546.7.1 Aggregation in Polar Organic Solvents 1556.7.2 Micelles in Nonpolar Solvents 1557 Beyond Micelles: Higher Level Self-Assembled Aggregate Structures 1617.1 The Importance of Surfactant Phase Information 1617.2 Amphiphilic Fluids 1637.2.1 Liquid Crystalline, Bicontinuous, and Microemulsion Structures 1637.2.2 “Classical” Liquid Crystals 1657.2.3 Liquid Crystalline Phases in Simple Binary Systems 1667.3 Temperature and Additive Effects on Phase Behavior 1707.4 Some Current Theoretical Analyses of Novel Mesophases 1717.5 Vesicles and Bilayer Membranes 1717.5.1 Vesicles 1737.5.2 Polymerized Vesicles 1747.6 Biological Membranes 1767.6.1 Some Biological Implications of Mesophases 1767.6.2 Membrane Surfactants and Lipids 1777.7 Microemulsions 1797.7.1 Surfactants, Co-surfactants, and Microemulsion Formation 1837.7.1.1 Ionic Surfactant Systems 1837.7.1.2 Nonionic Surfactant Systems 1847.7.2 Applications 1858 Surfactant Self-Assembled Aggregates at Work 1878.1 Solubilization in Surfactants Micelles 1888.1.1 The “Geography” of Solubilization in Micelles 1898.1.2 Surfactant Structure and the Solubilization Process 1918.1.3 Solubilization and the Nature of the Additive 1948.1.4 The Effect of Temperature on Solubilization Phenomena 1968.1.5 The Effects of Nonelectrolyte Solutes 1978.1.6 The Effects of Added Electrolyte 1988.1.7 Miscellaneous Factors Affecting Micellar Solubilization 1998.1.8 Hydrotropes 1998.2 Micellar Catalysis 2018.2.1 Micellar Catalysis in Aqueous Solution 2018.2.2 Micellar Catalysis in Nonaqueous Solvents 2039 Polymeric Surfactants and Surfactant–Polymer Interactions 2059.1 Polymeric Surfactants and Amphiphiles 2059.2 Some Basic Chemistry of Polymeric Surfactant Synthesis 2079.2.1 The Modification of Natural Cellulosic Materials, Gums, and Proteins 2079.2.2 Synthetic Polymeric Surfactants 2089.3 Polymeric Surfactants at Interfaces: Structure and Methodology 2139.4 The Interactions of “Normal” Surfactants with Polymers 2149.4.1 Surfactant–Polymer Complex Formation 2159.4.2 Nonionic Polymers 2189.4.3 Ionic Polymers and Proteins 2199.5 Polymers, Surfactants, and Solubilization 2229.6 Surfactant–Polymer Interactions in Emulsion Polymerization 22310 Emulsions 22510.1 The Liquid–Liquid Interface 22610.2 General Considerations of Emulsion Stability 22710.2.1 The Lifetimes of Typical Emulsions 23010.2.2 Theories of Emulsion Stability 23210.3 Emulsion Type and the Nature of the Surfactant 23310.4 Surface Activity and Emulsion Stability 23510.5 Mixed Surfactant Systems and Interfacial Complexes 23910.6 Amphiphile Mesophases and Emulsion Stability 24210.7 Surfactant Structure and Emulsion Stability 24510.7.1 The Hydrophile–Lipophile Balance (HLB) 24510.7.2 Phase Inversion Temperature (PIT) 25010.7.3 Application of HLB and PIT in Emulsion Formulation 25110.7.4 The Effects of Additives on the “Effective” HLB of Surfactants 25310.8 Multiple Emulsions 25410.8.1 Nomenclature for Multiple Emulsions 25410.8.2 Preparation and Stability of Multiple Emulsions 25410.8.3 Pathways for Primary Emulsion Breakdown 25510.8.4 The Surfactants and Phase Components 25611 Foams and Liquid Aerosols 25911.1 The Physical Basis for Foam Formation 26011.2 The Role of Surfactant in Foams 26311.2.1 Foam Formation and Surfactant Structure 26611.2.2 Amphiphilic Mesophases and Foam Stability 26811.2.3 The Effects of Additives on Surfactant Foaming Properties 26911.3 Foam Inhibition 27111.4 Chemical Structures of Antifoaming Agents 27211.5 A Summary of the Foaming and Antifoaming Activity of Additives 27311.6 The Spreading Coefficient 27411.7 Liquid Aerosols 27611.7.1 The Formation of Liquid Aerosols 27611.7.1.1 Spraying and Related Mechanisms of Mist and Fog Formation 27611.7.1.2 Nozzle Atomization 27711.7.1.3 Rotary Atomization 27811.7.2 Aerosol Formation by Condensation 27911.7.3 Colloidal Properties of Aerosols 28211.7.3.1 The Dynamics of Aerosol Movement 28211.7.3.2 Colloidal Interactions in Aerosols 28412 Solid Surfaces: Adsorption, Wetting, and Dispersions 28712.1 The Nature of Solid Surfaces 28712.2 Liquid Versus Solid Surfaces 29012.3 Adsorption at the Solid–Liquid Interface 29112.3.1 Adsorption Isotherms 29212.3.2 Mechanisms of Surfactant Adsorption 29312.3.2.1 Dispersion Forces 29412.3.2.2 Polarization and Dipolar Interactions 29512.3.2.3 Electrostatic Interactions 29612.3.3 The Electrical Double Layer 29712.4 The Mechanics of Surfactant Adsorption 29812.4.1 Adsorption and the Nature of the Adsorbent Surface 29912.4.2 Nonpolar, Hydrophobic Surfaces 29912.4.3 Polar, Uncharged Surfaces 30012.4.4 Surfaces Having Discrete Electrical Charges 30112.5 Surfactant Structure and Adsorption from Solution 30312.5.1 Surfaces Possessing Strong Charge Sites 30312.5.2 Adsorption by Uncharged, Polar Surfaces 30612.5.3 Surfactants at Nonpolar, Hydrophobic Surfaces 30612.6 Surfactant Adsorption and the Character of Solid Surfaces 30712.7 Wetting and Related Phenomena 30812.7.1 Surfactant Manipulation of the Wetting Process 31112.7.2 Some Practical Examples of Wetting Control By Surfactants 31412.7.3 Detergency and Soil Removal 31412.7.4 The Cleaning Process 31412.7.5 Soil Types 31512.7.6 Solid Soil Removal 31612.7.7 Liquid Soil Removal 31712.7.8 Soil Re-deposition 31812.7.9 Correlations of Surfactant Structure and Detergency 31912.7.10 Nonaqueous Cleaning Solutions 32012.8 Suspensions and Dispersions 32113 Special Topics in Surfactant Applications 32313.1 Surfactants in Foods 32313.1.1 The Legal Status of Surfactants in Food Products 32413.1.2 Typical Food Emulsifier Sources 32413.1.3 Chemical Structures of Some Important Food Emulsifiers 32613.1.3.1 Monoglycerides 32613.1.3.2 Derivatives of Monoglycerides 32713.1.3.3 Derivatives of Sorbitol 32913.1.3.4 Polyhydric Emulsifiers 33013.1.3.5 Polyglycerol Esters 33113.1.3.6 Sucrose Esters 33113.1.3.7 Anionic Food Emulsifiers 33213.1.3.8 Lecithin 33313.2 Some Important Functions of Surfactants in Food Products 33413.2.1 Emulsifiers as Crystal Modifiers in Food 33513.2.2 Bakery Products 33713.2.2.1 Anti-staling Agents 33813.2.2.2 Starch–Emulsifier Complexation 33913.2.2.3 Dough Strengtheners 34013.2.2.4 Aerating Agents 34113.2.3 Emulsifier Use in Dairy and Nondairy Substitutes 34213.2.3.1 What Makes Milk “Milk”? 34313.2.3.2 Surfactant Uses in Cheeses and Cheese Substitutes 34413.2.3.3 Surfactant Use in Deserts and Yogurts 34413.2.3.4 Butter and Margarine 34413.2.3.5 Whipped Cream and Nondairy Whipped Toppings 34513.2.3.6 Dairy Drinks 34713.2.3.7 Ice Cream 34713.2.3.8 Coffee Whiteners 34813.2.4 Protein Emulsifiers in Foods 34913.2.4.1 Proteins as Foam Stabilizers 35113.2.4.2 Proteins as Emulsifying Agents 35213.2.4.3 Protein–Low Molecular Weight Emulsifier Interactions 35313.3 Pharmaceutical and Medicinal Applications 35413.4 Petroleum and Natural Gas Extraction 35513.4.1 Enhanced Oil Recovery 35613.4.2 Hydraulic Fracturing or “Fracking” 35813.5 Paints and Surface Coatings 35913.5.1 Interfaces in Paints and Coatings 36013.5.2 Wetting and Dispersing Additives 36113.5.3 Wetting Agents 36313.5.4 Dispersing Agents 36313.5.5 Surface Wetting with Silicone Surfactants 36614 “Multiheaded” Amphiphiles: Gemini and Bolaform Surfactants 36914.1 Two (or More) Can Be Better Than One 36914.1.1 Structural Characteristics of Gemini Surfactants 37014.1.2 Some Synthetic Pathways to Gemini Structures 37114.1.3 Important Surfactant Properties of Gemini Surfactants 37214.1.4 Some “Outside the Box” Potential Applications of Gemini Surfactants 37514.2 Bolaform Surfactants 37714.3 Chemical Structures and Self-Assembly Patterns 380Chapter Bibliographies 381Index 389